On several websites, I have seen a letter from Marco Pollo to Headmaster Ambrose. He thanks him for helping him get to El Dorado and thanks Gamma for his mathmatical calculations to find the stormgate. I have also seen Wizard City while traveling through the stormgate.
With this evidence, I conclude we might go to Wizard City while searching for El Dorado. If that happens, wouldn't we be able to see players from Wizard 101 or will it still be on a separate database?

Kai Alcott on Feb 24, 2014 wrote:

Well, they use the same code languages as far as I know, but remember this: THEY'RE COMPLETELY DIFFERENT GAMES. Pirate101 probably doesn't have all the right data to display the wizard appearances and names, and wizard doesn't have Pirate data for ships and clothes and names. It would take a big update to add a new world, and ALL the wizard gear and wands and names. Plus, Wizard City didn't have a dock, if I remember right.

Actually, Wizard City does have a small dock, it's in Old Town where Baldur the trader from Grizzelheim is.

However, Blind Mew has said that for many reasons, Pirate101 and Wizard101 will never mix. It's not just about the coding language, or the amount of new items that would be added, it's also about the storage space, and how the two games run differently. The greatest problem I would see is how wizards and pirates fight differently in the games. What would a wizard's arcane battle circle look like to a pirate who wants to join in, or how would stationary wizards deal with a bunch of hyperactive pirates and their companions running around a battle board.
Really, it would just be too difficult for either team to join these games into one single game.